I would like to create a settings page for a user which allows them to save the options of a list which is to be used in a custom form. The list is called marketing source and it is added to a form which gets submitted with plain text values to an external API.
I know in field config for select lists you can do this but I want to do it on a custom config page for that specific list.
Foe example I would have a textfield in the config that had values like this
Then I need to convert that into a seralised array and store with variable set.
Is there a function that does that already for the field form?